Microwave-Assisted Bitumen Extraction With Vacuum-Assisted Sediment Filtration

Abstract

Method for characterizing a heavily biodegraded oil sand ore sample by microwave-assisted bitumen extraction. Vacuum-filtration of solvent-extracted bitumen and sediments provides a means to recover sediment fines down to a particle size of 0.8 μm, which is the analytical requirement for accurate mineralogical analysis of the clay mineral fraction. The method may be completed in hours, making it suitable for “just-in-time” analyses at the mine site. The recovered sediment and sediment fines are suitable for characterization using traditional analytical techniques to understand mineralogy, petrology, and reservoir properties.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]This application claims the benefit of U.S. Provisional Application Ser. No. 62 / 066,203, filed Oct. 20, 2014, entitled MICROWAVE-ASSISTED BITUMEN EXTRACTION WITH VACUUM-ASSISTED SEDIMENT FILTRATION, the disclosure of which is incorporated herein by reference.FIELD OF THE INVENTION[0002]This disclosure relates generally to the field of geophysical prospecting for hydrocarbons and, more particularly, to oil sand evaluation. Specifically, the disclosure relates to a method for microwave-assisted extraction of bitumen from oil sands for characterization of the oil sands.BACKGROUND OF THE INVENTION[0003]Geochemical analyses of bitumen and sediments from highly biodegraded oil sand samples presents substantial business and analytical challenges for routine characterization. Access to data from rapid, reliable characterization of oil sands bitumen and sediment is critical to daily operations and business decisions. Some laboratories may lack the...

AI Technical Summary

Benefits of technology

This patent describes a method for characterizing oil sand by heating a sample of oil sand in a microwave and then collecting the bitumen that has been separated from sediment and sediment fines through vacuum-assisted filtering. The sediment and sediment fines are then analyzed for mineral characterization. The technical effect of this method is that it allows for easier analysis of oil sand samples and the separation of bitumen from sediment.

Problems solved by technology

Geochemical analyses of bitumen and sediments from highly biodegraded oil sand samples presents substantial business and analytical challenges for routine characterization.

Some laboratories may lack the capability or turn-around time to adequately provide data on a daily basis.

Conventional geochemical extraction techniques are limited by the high level of bitumen saturation in oil sands samples and the decreased solubility of the asphaltene-rich bitumen in traditional organic solvents, requiring substantial time and solvent volume requirements in order to provide quantities of extracted sediment suitable for characterization.

Standard geochemical extraction techniques, such as Soxhlet or Soxtec extractions, are limited in their extraction efficiency by the azeotropic boiling point of the solvent mixture under normal conditions.

High levels of bitumen saturation (e.g., greater than 1%) in oil sand samples, combined with the decreased extraction efficiency of conventional techniques, can require substantial time (e.g., days to weeks) and solvent requirements (e.g., greater than 1 liter) in order to provide quantities of extracted sediment suitable for characterization (e.g., greater than 10 grams).

However, little work has focused on the direct analysis of petroleum hydrocarbons, in particular oil sands bitumen composition, using microwave extraction techniques.

However, these experiments were performed in a solvent-free system and relied only on in-situ sample water for heating.

Despite the amount of research into microwave technology in the separation of oil sands, these separation recoveries using these techniques have only been qualitatively reported and are unlikely to be robust enough for geochemical or mineralogical characterization of the resulting bitumen or mineralogy despite extensive analytical research in other fields that suggests microwave extractions may be more robust than traditional extraction techniques.

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